Using preparations of the nervous system of the barnacle, Balanus cariosus, the overall objective of the proposed research is to describe the neural basis of behavior in this relatively simple system. The techniques to be used to accomplish this objective include: a) Standard electrophysiological techniques including intracellular recording from identifiable populations of neurons in the ventral ganglion. b) Development and exploitation of relatively intact preparations to permit associating single neurons with particular muscles. c) Utilize the relatively intact preparations to investigate the role of sensory feed-back in shaping motor output. d) Determine the mechanism of the generation of bursting patterns seen in particular neurons in the barnacle central nervous system by using current passing techniques, altering the ionic environment, and pharmacological methods.